Micronutrients: Types, Functions, Benefits and More

Micronutrients are one of the major groups of nutrients your body needs. They include vitamins and minerals.

Vitamins are necessary for energy production, immune function, blood clotting and other functions. Meanwhile, minerals play an important role in growth, bone health, fluid balance and several other processes.

This article provides a detailed overview of micronutrients, their functions and implications of excess consumption or deficiency.

Summary Micronutrients can be divided into four groups — water-soluble vitamins, fat-soluble vitamins, macrominerals and trace minerals. The functions, food sources and recommended intakes of each vitamin and mineral vary.

All micronutrients are extremely important for the proper functioning of your body.

Consuming an adequate amount of the different vitamins and minerals is key to optimal health and may even help fight disease.

This is because micronutrients are part of nearly every process in your body. Moreover, certain vitamins and minerals can act as antioxidants.

Antioxidants may protect against cell damage that has been associated with certain diseases, including cancer, Alzheimer’s and heart disease (35, 36, 37).

For example, research has linked an adequate dietary intake of vitamins A and C with a lower risk of some types of cancer (4, 5).

Getting enough of some vitamins may also help prevent Alzheimer’s disease. A review of seven studies found that adequate dietary intake of vitamins E, C and A is associated with a 24%, 17% and 12% reduced risk of developing Alzheimer’s, respectively (6, 38).

Certain minerals may also play a role in preventing and fighting disease.

Research has linked low blood levels of selenium to a higher risk of heart disease. A review of observational studies found that the risk of heart disease decreased by 24% when blood concentrations of selenium increased by 50% (39).

Additionally, a review of 22 studies noticed that adequate calcium intake decreases the risk of death from heart disease and all other causes (40).

These studies suggest that consuming enough of all micronutrients — especially those with antioxidant properties — provides ample health benefits.

However, it’s unclear whether consuming more than the recommended amounts of certain micronutrients — either from foods or supplements — offers additional benefits (41, 42).

Summary Micronutrients are part of nearly every process in your body. Some even act as antioxidants. Due to their important role in health, they may protect against diseases.

Micronutrients are needed in specific amounts to perform their unique functions in your body.

Getting too much or too little of a vitamin or mineral can lead to negative side effects.

Deficiencies

Most healthy adults can get an adequate amount of micronutrients from a balanced diet, but there are some common nutrient deficiencies that affect certain populations.

These include:

Vitamin D: Approximately 77% of Americans are deficient in vitamin D, mostly due to lack of sun exposure (43).

Vitamin B12: Vegans and vegetarians may develop vitamin B12 deficiency from refraining from animal products. Elderly individuals are also at risk due to decreased absorption with age (44, 45).

Vitamin A: The diets of women and children in developing countries often lack adequate vitamin A (46).

Iron: Deficiency of this mineral is common among preschool children, menstruating women and vegans (47, 48).

Calcium: Close to 22% and 10% of men and women over 50, respectively, don’t get enough calcium (49).

The signs, symptoms and long-term effects of these deficiencies depend on each nutrient but can be detrimental to the proper functioning of your body and optimal health.

Toxicities

Micronutrient toxicities are less common than deficiencies.

They are most likely to occur with large doses of the fat-soluble vitamins A, D, E and K since these nutrients can be stored in your liver and fatty tissues. They cannot be excreted from your body like water-soluble vitamins.

A micronutrient toxicity usually develops from supplementing with excess amounts — rarely from food sources. Signs and symptoms of toxicity vary depending on the nutrient.

It’s important to note that excessive consumption of certain nutrients can still be dangerous even if it does not lead to overt toxicity symptoms.

One study examined over 18,000 people with a high risk of lung cancer due to past smoking or asbestos exposure. The intervention group received two types of vitamin A — 30 mg of beta-carotene and 25,000 IU of retinyl palmitate a day (50).

The trial was halted ahead of schedule when the intervention group showed 28% more cases of lung cancer and a 17% greater incidence of death over 11 years compared to the control group (50).

Micronutrient Supplements

The safest and most effective way to get adequate vitamin and mineral intake appears to be from food sources (51, 52).

More research is needed to fully understand the long-term effects of toxicities and supplements.

However, people at risk of specific nutrient deficiencies may benefit from taking supplements under the supervision of a doctor.

If you’re interested in taking micronutrient supplements, look for products certified by a third party. Unless otherwise directed by a healthcare provider, be sure to avoid products that contain “super” or “mega” doses of any nutrient.

Summary Since your body requires micronutrients in specific amounts, deficiencies and surpluses of any one nutrient may lead to negative issues. If you’re at risk of a specific deficiency, talk to your doctor before starting supplements.